c# - creating form inside webforms.aspx -

i newbie asp.net webform. how create form inside asp.net webform page .i tried create follow not working

<form id="form1" runat="server">         <div>             <form name="user_detail">           </form>         </div>     </form> 

you can remove the

<form name="user_detail"> </form>

you can name main form user_detail